<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>CSS练习</title>
<!--    style标签专门用来定义CSS样式代码-->
    <style type="text/css">
        /*CSS注释*/
        div{
            border: 1px red solid;
        }
        span{
            border: 1px red solid;
        }
    </style>
</head>
<body>
    <div>div标签1</div>
    <div>div标签2</div>
    <span>span标签1</span>
    <span>span标签2</span>
</body>
</html>